Ok you UDS gurus, this one is right up your alley. I've built several UDS recently, and I would like to think I at least have an understanding of how they work. Each of my first 4 drums was built using four 1" intakes using either 3/4 nipple valves and caps/ball valves or flexable magnets over the holes to regulate temperature. My recent dilema is this: Today I made two breakfast fatties, fired up the smoker and cooked. This smoker (#5, see previous postings for burn tests and whatnot using smaller intakes) has four 3/4 holes and uses magnets to cover the holes and regulate temperature, no biggie, been smoking on this one at work for over a month now, probably about 10 times or so. Today after I cooked on it, I pulled the meat around noonish and covered the vents completely and put the lid back on didn't cap the exhaust. Went outside just a bit ago (around 3pm CST) and the temp was holding at 200-210 degrees with no other primary intakes open. The lid isn't exactly an airtight seal, but it seals evenly all the way around. Is there any reason why with it using the exhaust as both a air draw/exhaust push that I couldn't cook on it as it is and not experience any temperature fluctuations and for it to maintain the same temperature that it's holding now?